Apparatus for treating leather



June 4, 1929. J. A. MxLmcAN 1,716,076

' APPARATUS FOR TRETING LEATHER Original Filed Feb. 1, 1927 f' |55 gl/@@Lom l t v gvwentoz Jamea AndrewMiHican Patented .lune d, 1929.

AUNIT JAMES ANDREW lVIILLICAN, `0F -DETROIT, MICHIGAN.

APPARATUS FOR TREATING LEATHER.

Original application filed February 1, 1927, Serial No. 165,204. Divided and this application :filed August My present invention relates to the manufacture of leather. n

The subject matter of this invention is ra division of my application filed lieb. l, l92( as Serial Number 165,204.

The purpose of this invention 1s to provide improved apparatus for the treatment and particularly the setting-out and the drying of leather.

t has long been recognized that allowing leather to dry without holding it stretched out results in a great shrinkage of the leather and that allowing the leather to dry without its being in some way held flatallows the -leather to become permanently wrinkled or` curved. To obviate this shrinkage and wrinkling the pieces of leather were tacked or otherwise positively fastened to the setting-out board or other form and left in that position until dry. rlhat method held the leather from shrinking at the holding tacks or nails, but allowed some shrinking between and often left wrinkles and always left nail holes which necessitated trimming th-e edges of the piece of leather.

Another method of treatingr leather at this stage of its manufacture contemplated ythe setting-out of the leather wet upon the setting-out board and relying upon `the adhesion of theleather to the board to keep the leather stretched out and flat during the .dry-

ing process. TvVith many common forms of leather this method was not successful because the leather loosened from the settingout board before the leather had dried pastl To over- A come that dithculty an adhesive was applied the shrinking and wrinklin g state.

either .to the setting-out board or other drying; surface or to the hide itself so as to make the leather stick or adhere to the said surface without shifting or shrinking.

rlhe use of an adhesive upon or in connection with the leather, however, has in many cases an injurious effect upon the leather and in practical-ly all cases prevents the leather from being when dried of as good quality would have been the .case if no adhesive had been used. l have Vfound also that in many;

cases when the leather was treated supposedly under the process of placing thc leather wet upon the setting-out board and supposedly without using an adhesive, the eiiicacy ofthe process really resided in the fact that some ofthe oils 0r other materials previously used .in the treatment ofthe hide were actually Serial No. 214,200.

operative as an adhesive and that the use of such material was continued because itL seemed to aid in the, drying process.

It is one purpose of my invention to provide means or apparatus that will overcome or obviate the objections :and disadvantages incident to the manufacture of leather as above mentionedand to provide lmeans whereby practically any type of leather may be dried upon the setting-out board withoutthe use of an adhesive and without utilizing any material in the leather that would `act as anv adhesive and without having to puncture the leather with nails or other holding devices.

Another purpose isto provide means for treating leather in the use of which the capillary attraction ofthe water meisten-ed` leather is relied upon to hold the leather to the setting-out board as long as necessary to produce a drying of the leather without wrinkling and wherein means are used to assist said capillary attraction or to continue the said capillary attraction at the edges of the leather until .the whole piece of leather is evenly dried. l

As a general average when leather comes to this stage ready for setting out and dryingmfty per cent of its gross weight is'water. Of this fty part-s water, forty parts dry out without any noticeable tendency of the leather vto shrink but then the contraction stage is reached and during the drying against shrinking, would shrink from fifteen per cent to eighteen per cent of its original area. The remaining` five parts of water stayv in the leather in its usual commercial form. For convenience of description herein I will refer to the part of the drying out. when contraction of the leather is taking place as J the final drying out or contraction` period and will refer to the previous drying out as the primary drying period. l have found that the processes which hold the hide upon the setting out board or other formv positively until the drying process is entirely complete and without allowing any shrinkage whatever produces a lower grade or an Vinferior quality of leather7 but that allowing the-leather to shrink somewhat, say three per cent of its area, retains or'improves the quality of the leather so as Ito far outweigh the slight. shrinkage allowed. a further purpose of my invention'is to pro- Accordingly said edges to leave the surface of the settingout board and curl up and so successively expose to premature drying successive portions of the. leather in from the edge resulting in uneven drying` and curling of the leather. My invention provides means to Vovercome this trouble and to hold the edges of the leather against the setting-out board until the whole piece of leather' is dried and thus prevent. the admission of air to the space between the leather and the setting-out board and so prevent drying out from the gi side ofthe leather. The use of my apparatus contemplates that the leather have its grain side heldclose enough to the settingout board to prevent the leather curling up at the edge or drying out from the grain side.

It. is a further purpose of my invention to provide means or apparatus of such character as will hold the leather and especially the edges thereof closely against the board during the entire drying period but will allow the leather to shrink somewhat but much less than the normal amount during the final drying period with the leather, however, still held flat and even during said final drying period.V

A further-purpose is to provide convenient holding and pressure exerting mechanism that can be readily applied to the setting out board at any desired positions so that pieces of leather vof any size or shape may be treated.

Further purposes and advantages ofY my invention will appear from the specilication and claims herein. v

Fig. l of the drawings is a plan view ofv said hide,

Referring to the drawings in a more particular description it will be seen that I am vutilizing a setting-out board l0 having the Vusual hard and relatively impervious upper surface ll necessary for suchsetting-out board to dry the hide 12 upon.l The hide in a wet condition is set out in the usual manan adiacent ieee of the right handV nl Fig. 3 a sectional view` on line 3 3 of o, f b

ner upon the setting-out board 10 with the hide stretched out as is usual to the proper extent upon the board through the settingout process. Incident to the wetness or moisture of the hide and the pressure used in setting-out the hide upon the board the hide sticks or adheres very closely to the settingout board when first placed thereon. This sticking of the grain side of the leather to the setting out board I take Care shall be due simply to the wetness yof the hide and the pressure used in setting out the hide upon the board which two factors produce a form of capillary attraction and particularly I see to it that the leather and the board are free from any adhesive material. In order to be sure that the leather after it has been colored comes to this process free of adhesive material or at least free from any adhesive action of any adhesive in the leather I remoisten or wash the leather in warm water. This warm water removes any adhesive present in the leather or at least neutralize `any adhesive action of any adhesive material left in the leather. This washing in warm water is done iinmediatey beforey setting out the leather upon the board. l

After the leather has been thus set out upon the board I employ apparatus to hold the edges of the leather closely to the setting-out board until the entire drying process is complete; that is until the leather has stayed upon the board long enough for that portion of the water which is to be extracted has dried out from the leather. The holding of 'the edges of the leather thus closely to the board prevents the said edges'froin curling up and prematurely drying and curling at the edge and especially prevents the leather from drying out at the edge and then curling and successively exposing other Zones of the leather close to the edge to premature drying upon the grain side of the leather. In other words the holding of the edges of the leather closely tothe board until the leather is entirely dry assists the holding action due to the wetness of the leather and the capillary attraction therein so that the whole area ldries evenly.

Preferably also the means that I employ to hold the edges of the leather closely to the board also operate by a yielding tension and a yielding holding action upon the leather so as to hold the leather extended against the greater part of the shrinkage. that would normally take place during the contraction stage of drying, but said resilient holding'V machanisin is of such form and arrangement as to allow a small part of the normal shrinkage to take place without the leather slipping from or becoming free ofv said holding mechanism.

Preferably also said holding mechanism should be simple and economical in construction and operation and constructed in small units and readily attachable :to any part 4of the setting out board Without puncturing or injuring the surface of said board. The preferred form of a holding means that will iill these requirements is a suction-basedspring armed clip generally `denoted bythe numeral 13. A lplan lview of two of these clips is shown in Fig. 2 and a vertical sectional View of one of them is shown in Fig. 3. This clip has a conventionally formed suction-.operating or vacuum-operating base i14; usually made of rubber orsomesim'ilar material and is concavo-convex or saucer shape in vcross section. To lthe topof this base is secured the mot-al `frame 15 preferably With a rubber o r other yielding boss 16 above the frame -15 and a metal Washer 17 labove said boss with the central metal connecting meinberrof the device commonly terminating v above the Washer in an eye 18.

rlhe frame 15 is conveniently7 formed of resilient sheet metal preferably having tivo spaced arms 19 adapted to iextend past the base 1/1- over the edge of the adjacent piece of leather as lWill :be apparent from Fig. 2. Towards their outer ends these arms are turned `or curved downwardly'more or less as shown in Fig. 3. Opposite the arms 19 the meta-l frame is provided With an anchoring arm 20 which extends beyond the edge of the suction base and is .turned down to Irest against the surface 11 of the-setting out board to aid in the clip maintainingvits resilient pressure upon the leather through the two arms 19. In practice the Working arms 19 may be spaced about two inches apart from center to center and these holding clips may be placed along the edge of the leather at intervals so as to have the space from the center of one arm of one clip to the center of an arm on an adjacent clip about tufo inches. It Will be understood that this suggestion of size of the clips and spacing of the clips along the side of the leather is simply illustrative and. that the clips may be larger or smaller and of different shape and may be spaced closer together or farther apart according to the requirements of the different leather being treated.

In 1 l have shown a hide 12 set out upon the setting-out board 10 and upon the board has been placed a number of these holding devices. lt will be understood of course that a sufficient number of these holding devices are employed to reach all the vvay around the outer edge of the hide. It will be particularly noticed that these holders or clips 13 are readily adjustable in any point upon the setting-out board so that they can be placed upon the board ust outside the hide and thus adapt the apparatus to operate upon any size of hide and upon any shape or size of the piece of leather that may go upon the setting-out board. It Will be understood further that the application of the suctionbased .clips V:to .the setting-.out '.board .does not 'ency of the holding arms 19 is such that :the

edges of the leather are held .closely to the setting-.out board during the ventire process of drying. The ftensionofthe vholding arms 19 is also such that theusual `large Lamount of shrinkage ,of the leather is largely .restrainedbut not entirely prevented in that about a fifth or a sixt-hof the normalshr-inkage is permitted; that is a shrinkage to the extent of about Jthree .per cent `of the total areavof-the leather is allowed during the contraction period by reason ofthe leather sliding beneath the arms 19 but ynot sliding ,entirely from beneath said arms 19. 1n `Fig. r2 in full lines is shown theoutlineof a piece of leather 12 with the outer edge 21shoxvn also in full lines 'in the position' itfoccupiesre'lative to .the clips when the tleather .is first yset out upon the board and the .clips 'applied thereto. After :the slight allotved'shrinkage of the 'leather has 'taken place :this outeredge 21 of the leather'wil'l have moved relative to the arms '19 and to the adjacent partof the surface of the setting-out board about to the dashed line 22-22. It Will be understood of course that the other outer edges of the hide have shrunk in the same Way to a greater or less extent according to the character of the hide and the location of the part in question upon the hide; It Will be understood furthermore that the clips may if necessary be located at other than a direct right angle to the adjacent edge of the hide in order to hold in a most effective Way against the shrinkage of the hide and also to allow of some side- Wise motion of the leather past the clips if such sidewise motion is not sufficiently allowed for through the permitted pivotal action of the metal frame 15 upon the base 14.

l/Vhat I claim as new and desire to secure by Letters Patent is:

1. Mechanism for treating leather comprising a setting-out board and a plurality of devices located outside the area of the leather on the board and having spring tensioned arms adapted to extend over the edge of theV leather and hold the edges of the| leather closely to the board during the drying period by pressing said edges against the board.

2. Mechanism for treating leather comprising a. setting-out board and a. plurality of devices located outside the area of the leather on the board and having yieldingly tensioned arms adapted to extend over the edges of the leather and hold the leather closely to the board during the drying period by pressing said edges against the board.

3. Mechanism for treating leather comprising a setting-out board and a plurality of devices located outside the area of the leather on the board and having yieldingly tensioned arms adapted to extend over the edge of the leather and hold the leather closely to the board during the drying period and tensioned to hold the leather from the greater part of its normal shrinkage but to allow a part of such shrinkage.

4. Mechanism for treating leather comprising a setting-out board and a plurality of devices adapted to be removably secured to the setting-out board outside the area of the leather and having yieldingly tensioned arms to extend over the edge of the leather and hold the leather closely to the board during the drying period and be tensioned to hold the leather from the greater part oii its normal shrinkage but to allovvla `part of such shrinkage. Y

5. Mechanism for treating leather comprising a setting-out board and a plurality of suctioned-basedv devices adapted to be removably secured .to the setting-out board outside the area of the leather and having yieldingly tensioned arms to extend over the edge'of the leather and engage the saine.

6. Mechanism for treating leather comprisingan imperiforate, plain-surfaced settingout board and a plurality of devices having suction-cup bases whereby the devices are adapted to be removably secured by suction l to the said setting-out board outside the area of the leather, said devices having springtensioned arms to extend over the edges of the leather and press the said edges against the board andhaving an anchoring arm extending in the opposite direction and engaging the board outside the leather and adapted to prevent said suction cup bases from being tipped over. 1

7. Mechanism for treating leather comprising an imperforate plain-surfaced settingout board and a plurality o-devices having suction-cup vbases whereby the devices are adapted to be removably secured to the setting-out board outside the area of the leather, said devices having yieldingly tensioned arms adapted to extend over the edges oi' the leather and hold the edges of the leather closely to the board during the drying period, said tension being sufficient to hold the leather against slipping during the preliminaryV drying stage, but to allow some slipping during the iinal drying 'of the leather, said devices having counterbalancing arms extending back over and into engagement with the board away from the leather and adapted to prevent said suction cup bases from being tipped over.

In witness whereof `l have aiiixed my signature, this 25th day of July. 1927.

JAMES ANDRETV MILLCAN. 

